Burner control device



Oct. 4, 1966 o. w. MICKO 3,276,506

BURNER CONTROL DEVI CE Filed June 1, 1964 INVENTOR O8 WHLO w urn M cm BY Age/4w @447) ATTORNEYS United States Patent 0 3,276,506 BURNER CONTROL DEVICE Oswald Walter Micko, Geislingen Steige, Germany, assignor t0 Apparatebau Eugen Schrag Kommanditgesellschaft, Ebersbach, Fils, Germany Filed June 1, 1964, Ser. No. 371,610

Claims priority, application Germany, Dec. 19, 1963,

A 44,829 8 Claims. (Cl. 15828) The present invention relates to a supervisory system of burner units and especially to a gasor oil-fired burner unit with a flame monitoring and supervision by means of an ultra-violet diode or the like.

Numerous burner uni-ts with supervisory installations are known in the prior art which monitor and supervise the operation of the burner units, the presence of a flame and of an ignition spark or of a pilot flame. However, the measuring or sensing devices themselves are occasionally very prone to breakdown and failure and therefore have to be monitored and supervised themselves in order that they do not carry out any faulty control or erroneous switching operations and thereby, for example, supply gas to the burner rwhen neither the pilot flame nor the ignition sparks are present. In order to detect several different measuring magnitudes, as a rule several measuring instruments or sensers are required. The present invention aims at simplifying such types of supervisory installations and to constitute the same more safe and reliable. The present invention essentially consists in the application of an apertured disk producing rectangular pulses tor the supervision of burner units. Such a type of disk moving in an appropriate manner in front of the measuring or sensing apparatus which periodically covers and exposes this measuring or sensing apparatus, provides a situation where rectangular pulses are produced in the measuring or sensing apparatus, which pulses can be utilized for contnol purposes. Any errors or defects can then be determined very readily by the fact that in case of failure or breakdown, the pulse deviates or diflers from its intended form. Also, the shape of the rectangular pulses produced can be utilized for the measurement of different operating magnitudes. A very simple and safe means is thus introduced by the present invention for the supervision of burner units.

With a gasor oil-fired burner unit having a flame supervision by means of a diode sensitive to ultra-violet rays or the like, the present invention distinguishes itself by the fact that an apertured disk or the like is arranged in front of the UV diode or the like which periodically covers the diode. If the apertured disk is disposed between the flame and/ or ignition-spark spaces and diode, then a rectangular pulse is produced in the diode if the flame burns and/ or if the ignition spark is present. If neither flame nor ignition spark are present, or the diode, the apertured disk or the drive means thereof are defective, then the diode produces pulses deviating or difler-. ing from the desired intended form, which influence a control apparatus and signal and possibly utilize the defect.

The apertured disk or the like can be driven with constant velocity so that a desired and intended shape of the pulse is produced which always remains the same. However, according to the present invention, the apertured disk can also be driven in dependence on a magnitude to be supervised, for example, of the combustion air quantity. Then the shape of the pulses, for example, the length thereof, is a measure for the value of the magnitude to be monitored and supervised so that by means of the diode and the apertured disk, in addition to :fault supervision, simultaneously the supervision of an additional 3 ,276,506 Patented Oct. 4, 1966 quantity is made possible without providing additional measuring apparatus or sensing means.

The apertured disk can be driven rotatingly from a synchronous motor or in particular advantageous construction of the present invention may be driven by means of a type of wind wheel or impeller which is acted upon at least by a part of the combustion air. With such an arrangement, a measurement of the combustion air quantity is simultaneously made possible by means of the flame supervising diode.

With a particularly simple construction in. accordance with the present invention, the apertured disk itself is provided with blades, vanes, wings or the like. Then an additional wind wheel or the like for the drive of the apertured disk may be dispense-d with. Advantageously, the apertured disk or the like is disposed in the secondary air stream of a burner.

In a very simple construction according to the present invention, the UV diode and the apertured disk constructed as planar rotating disk are accommodated in a pot-shaped pipe or duct conducting and supplying secondary air and arranged on the inside of the burner. The ignition electrode can also be disposed Within the angle of vision of the UV diode covered by the aperture disk. Thus, a single UV diode can pnoduce pulses for three different measuring quantities, namely detection of the flame, detection of the ignition sparks and detection of the combustion air quantity. An extremely simple arrangement is produced thereby which otters a self-monitoring and auto-supervising operation.

Accordingly, it is an object of the present invention to provide a supervisory control system for burner units of the type described above which is extremely simple in construction, reliable in operation, yet avoids the shortcomings and drawbacks encountered with the prior art constnuctions.

Another object of the present invention resides in the provision of a control system for supervising burner units, especially gas or oil-fired burner units which prevents any faulty control due to breakdown or defective operation of component elements.

Another object of the present invention resides in the provision of a control system supervising the operation of burner units which make sure that fuel is supplied to the burner only in the presence of a pilot flame, a heating flame and/ or ignition sparks.

Still another object of the present invention resides in the provision of a supervisory control system monitoring and controlling the operation of burner units which obviates the need for separate measuring instruments and/ or sensing devices to monitor and oontrol different 0perating aspects and measuring quantities.

Still a further object of the present invention resides in the provision of a control system for monitoring and supervising burner units which permits ready determination of any faulty operation or defects and breakdowns in the system.

Another object of the present invention resides in the provision of a control system for monitoring and supervising burner units which is extremely simple, relatively inexpensive yet excels by extraordinary reliability and safety in operation.

A still further object of the present invention resides in the provision of a control system for burner units which permits monitoring of the flame and ignition sparks With a device capable at the same time to measure the comhustion air quantities supplied to the burner.

These and other objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illus- 'flame core.

tration only, two embodiments in accordance With the present invention, and wherein FIGURE 1 is a longitudinal cross sectional view through a first embodiment of a burner in a burner unit in accordance with the present invention;

FIGURE 2 is a diagrammatic showing of the pulses produced by the diode in the arrangement according to the present invention, and

FIGURE 3 is a partial cross sectional view, similar to FIGURE 1, of a second modified embodiment of a burner unit in accordance with the present invention.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIGURE 1, the burner shown therein is, for example, a gas burner which comprises an outer cylindrical pot-shaped casing 1, the bottom 2 of which has a dishor cup-shaped part 3 pressed-out in the rearward direction. The outer wall 1 becomes narrower or tapers in the direction toward the nozzle orifice in a part 4 thereof. A cylinder 5 is arranged on the inside of the burner which extends from the bottom 2 to the nozzle aperture of the burner and forms thereat a ring-shaped nozzle together with the part 4. The secondary air is supplied through the cylinder 5. The cylinder 5 is surrounded by an annularly shaped gas channel 6 to which gas is supplied through the pipe 7. The gas leaves this gas channel 6 through the apertures 8 into the mixing space or chamber 9. The gas is mixed within the mixing space 9 with primary air flowing into space 9 through the bores 10 provided in the bottom 2 and then reaches the nozzle aperture or orifice. The secondary air enters through apertures 11 in the bottom 2 of the cup-shaped part 3 and reaches through the cylinder '5 the flame forming to the left of the burner.

The ignition electrode 12 is arranged in the cylinder 5 from the inside thereof within the area of the nozzle aperture. The electrode 12 extends through the bottom 2 of the outer casing or envelope 1.

The UV diode 13 is arranged somewhat outside of the center Within the cup-shaped part 3 of the bottom 2 and is directed with the angle of vision or thereof toward the aperture of the cylinder 5 within the area of the nozzle orifice so that this angle of vision detects from the inside the flame forming to the left of the burner, that is, the Simultaneously, the electrode 12 with the sparking area thereof is disposed within the angle of vision on of the diode 13 so that the diode also detects ignition sparks.

The aperture disk 14 in accordance with the present invention is arranged concentrically or coaxially within the burner in front of the diode 13. In the illustrated embodiment, the aperture disk 14 is constructed as a flat disk rotating about the axis of the burner and provided with the aperture 15. The aperture 15 is so dimensioned that it periodically frees the entire angle of vision of the UV diode 13 and then again covers the same. In the illustrated embodiment, the aperture disk 14 is carried by a synchronous motor 16 and is driven with constant velocity. The synchronous motor 16 is arranged in the bottom of the cup-shaped part 3.

Operation,

The aperture disk 14 in accordance with the present invention brings about the following control effects:

When a flame has formed in front of the burner and the apertured disk 14 is driven with constant velocity, then a rectangular pulse is produced in the UV diode 13 as shown, for example, in FIGURE 2 and designated therein by reference numeral 17. An identical or similar rectangular pulse is formed also when the electrode 12 produces an ignition spark and the disk 14 rotates. This pulse signals to the control apparatus (not shown) of conventional construction that either the flame burns completely satisfactorily and all the other parts of the diode 13 and apertured disk 14 are in proper order, or that with satisfactory function of the diode 13 and of the apertured disk 14, an ignition spark is supplied. Known conventional control apparatus may then be actuated by means of these rectangular pulses to keep open, for example, the magnetic valve controlling the fuel, when the flame burns, or for example, to open initially the magnetic valve when an ignition spark is present. When the flame extinguishes or the ignition spark is extinguished and no flame burns, then the diode 13 produces the continuous pulse 18. When the diode 13 is defective, that is, it is burned out, then the pulse 18 is also produced. However, when the diode 13 produces a short-circuit and connects through, i.e., effectively opens a gating circuit, then it produces the pulse 19. Also when the apertured disk 14 stands still for any reason, the flame burns or the ignition operates, and the aperture 15 is just within the angle of vision of the UV diode 13, then the pulse 19 is also produced. However, if the apertured disk 14 stands still and covers the UV diode 13, then it again produces a pulse 18. If the velocity of the disk 14 does not correspond to the intended value, then the pulse 17 deviates from its normal intended shape. Thus, it can be determined from the shape of the pulse produced by the diode 13 whether the burner unit is in a completely satisfactory condition or whether any defects are present. The pulses are utilized in corresponding control apparatus in a known manner. The type of the pulse thereby even indicates the type of failure as may be readily understood from the three described and illustrated pulses.

The embodiment of FIGURE 3 is essentially similar to the embodiment of FIGURE 1, however, the apertured disk 14 in this embodiment is not driven by a synchronous motor, but is freely rotatably supported and is provided along the outer circumference thereof with guide blades or vanes 20. Since the disk 14' is disposed in the secondary air stream, it is set into rotation in dependence on the supplied secondary air quantity. Corresponding to the rotational speed of the aperture disk 14', the diode 13 produces, in the proper condition thereof, rectangular pulses of different length. The length of these rectangular pulses is therefore a measure of the supplied secondary air quantity. Thus, the secondary air quantity is simult-aneously detected by means of the diode 13. The length of the pulses can be utilized in a known, conventional manner for the control and/or indication of the secondary air quantity and/or for the control of the supplied air quantity.

While I have shown and described two embodiments in accordance with the present invention, it is understood that the same is not limited thereto, but is susceptible of numerous changes and modifications within the spirit and scope of the present invention. In particular, the arrangement according to the present invention of an apertured disk may also be used with burners of different construction, outside the burner, alongside and/or in front of the flame or at any other suitable place. Also, the present invention is not limited to the use of UV diodes, but may be utilized with other monitoring and supervisory elements which utilize a radiation. Furthermore, the particular arrangement need not be disposed in the secondary air stream; it may also be disposed, for example, Within the primary air stream. Moreover, the apertured disk may be driven by any other suitable means, for example, by an additional wind wheel or impeller. Additionally, the apertured disk need not be constructed necessarily as a flat rotating disk, but may be constructed also in any other manner as an element periodically covering the sensing device, for example, in the form of an apertured drum or the like or of a movable band or plate with a corresponding aperture or several apertures.

Thus, it is obvious that the present invention is not limited to the details shown and described herein, but is susceptible of numerous changes and modifications within the spirit and scope thereof, and I therefore do not wish to be limited to the details shown and described herein,

but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

I claim:

1. In a burner unit including a duct for application of combustion air to a nozzle, a flame monitoring and supervising system comprising radiation detector means for detecting the presence of a flame,

and means for periodically covering said radiator detector means including apertured disk means,

and driving means for driving said apertured disk means in dependence on the quantity of combination air supplied by said duct to said nozzle,

said drive means including impeller means on said apertured disc means acted upon at least by a part of the combustion air supplied by said duct to drive said apertured disc means.

2. In a burner unit, including means for applying combustion air to a nozzle, a flame monitoring and supervising system comprising radiation detector means for detecting the presence of a flame,

and means for periodically covering said radiation detector means including apertured disk means,

and driving means for driving said apertured disk means in dependence on the quantity of combustion air supplied by said means applying combustion air to the nozzle,

said apertured disk means being provided with peripheral blade means extending at an angle to the axis of rotation thereof for driving said disc means by means of said combustion air.

3. In a burner unit including a duct for application of secondary combustion air to a nozzle, 21 flame monitoring and supervising system comprising radiation detector means for detecting the presence of a flame,

and means for periodically covering said radiation detector means including apertured disk means,

and driving means for driving said apertured disk means in dependence on the quantity or" secondary combustion air supplied by said duct to said nozzle,

said drive means including impeller means on said apertured disc means acted upon at least by a part of the secondary combustion air,

and said apertured disk means being disposed at least in part in said duct in the secondary air stream.

4. In a gasor oil-fired burner unit including means for providing primary combustion air to a mixing chamber and a nozzle, a flame monitoring and supervising system comprising radiation detector means for detecting a flame,

means for periodically covering and exposing said detector means including apertured disc means,

and duct means arranged on the inside of the burner concentric with said nozzle for supplying secondary combustion air directly to said nozzle, said duct means being provided with a pot-shaped part in one end thereof opposite said nozzle, said detector means and apertured disc means being arranged in said potshaped part.

5. In a gasor oil-fired burner unit including means for providing primary combustion air to a mixing chamber and a nozzle, a flame monitoring and supervising system comprising radiation detector means for detecting a flame,

means for periodically covering and exposing said detector means including apertured disc means,

and driving means for driving said apertured disc means,

and duct means arranged on the inside of the burner concentric with said nozzle for supplying secondary combustion air directly to said nozzle, said duct means being provided with a pot-shaped part in one ti end thereof opposite said nozzle, said detector means and apertured disk means being arranged in said potshaped part,

and ignition electrode means disposed within the angle of vision of said detector means which is periodically covered by said apertured disc means.

6. In a gasor oil-fired burner unit including means for supplying primary combustion air to a mixing chamber and a nozzle, a flame monitoring and supervising system comprising radiation detector means including ultra-violet sensitive diode means for detecting a flame and igniton sparks,

means for periodically covering said detector means including apertured disc means,

and driving means for driving said apertured disc means,

and duct means arranged on the inside of the burner concentric wvith said nozzle for supplying secondary combustion air directly to said nozzle, said duct means being provided with a pot-shaped part in one end thereof opposite said nozzle, said detector means and apertured disk means being arranged in said potshaped part,

and ignition electrode means disposed within the angle of vision of said detector means which is periodically covered by said apertured disk means. '7. In a gas-fired or oil-fired burner unit including an annular mixing chamber, means for supplying fuel and primary combustion air to said mixing chamber and a central duct for supplying secondary combustion air, said mixing chamber and said duct being concentrically disposed and forming an annular nozzle opening therebetween, the improvement essentially consisting of a flame monitoring and supervisory system comprising:

radiation detector means including radiation sensitive diode means for detecting a flame and ignition sparks,

means for periodically covering and exposing said detector means including a rotatable apertured disc means,

said radiation detector means and apertured disc means means being mounted within said central duct with said apertured disc means being positioned between said diode means and said nozzle opening,

and ignition electrode means disposed within said central duct within the angle of vision of said detector means.

8. A burner unit as defined in claim 7, wherein said apertured disc means is provided with peripheral impeller means in the form of blades extending at an angle to the axis of rotation of said disc means for rotating said disc means by means of said secondary combustion air passing through said central duct, whereby the speed of rotation of said apertured disc is proportional to the flow rate of said secondary combustion air, so that pulses having a duration inversely proportional to secondary air flow rate are derived from said detector means.

References tCited by the Examiner UNITED STATES PATENTS 1,755,970 4/ 1930 Singleton.

1,996,233 4/1935 Darrah 158-28 2,339,754 1/1944 Brace 158-28 2,346,864 4/1944 Packard 73-239 2,804,131 7/1957 Ator 158-28 2,964,102 12/1960 Cassell et al. 158-28 2,969,672 1/1961 Sell et a1 73-239 JAMES W. WESTHAVER, Primary Examiner. 

4. IN A GAS- OR OIL-FIRED BURNER UNIT INCLUDING MEANS FOR PROVIDING PRIMARY COMBUSTION AIR TO A MIXING CHAMBER AND A NOZZLE, A FLAME MONITORING AND SUPERVISING SYSTEM COMPRISING RADIATION DETECTOR MEANS FOR DETECTING A FLAME, MEANS FOR PERIODICALLY COVERING AND EXPOSING SAID DETECTOR MEANS INCLUDING APERTURED DISC MEANS, AND DUCT MEANS ARRANGED ON THE INSIDE OF THE BURNER CONCENTRIC WITH SAID NOZZLE FOR SUPPLYING SECONDARY COMBUSTION AIR DIRECTLY TO SAID NOZZLE, SAID DUCT MEANS BEING PROVIDED WITH A POT-SHAPED PART IN ONE END THEREOF OPPOSITE SAID NOZZLE, SAID DETECTOR MEANS AND APERTURED DISC MEANS BEING ARRANGED IN SAID POTSHAPED PART. 